Portable sound recording and sound reproducing machine



P 1939. VON MADALER ET AL 2,173,043

PORTABLE SOUND RECORDING AND SOUND REPRODUCING MACHINE 4 Sheets-Sheet 1Filgd March 11, 1957 INVENTORS BY W2 71PM, ATTORNEY.

Sept. 12, 1939.

F. VON MADALER ET Al.

PORTABLE SOUND RECORDING AND SOUND REPHODUCING MACHINE Filed March 11,19257 4 Sheet sSheeC 3 Sept. 12, 1939. F. VON MADALER ET AL 2,173,048PORTABLE SOUND RECORDING AND SOUND REPRODUCING MACHINE I Filed March 11,1957 4 Sheets-Sheet .4

RECORDING HEAD 10.9 4 MOTOR 105 INVENTO Fig. 5 Q; WA

1 I ATTORNEY.

Patented Sept. 12, 1939 v PORTABLE SOUND RECORDING AND SOUND REPRODUCINGMACHINE Ferdinand von Madaler, West Hempstead, Long Island, and WilliamL. Woolf, Bayside, Long Island, N. Y., assignors to Film RecordingCorporation, a corporation of New York Application March 11, 1937,Serial No. 130,400

3 Claims. 01. 274- 11 This invention relates to a device for recordingsound vibrations on a strip of film for ref production purposes, andalso for reproducing sound from such a record.

' One of the objects of the invention is to provide a device of thisnature, small in dimensions,

neat in appearance, positive in action, and of .a form and design whichmay be readily and inexpensively manufactured.

Another object is to produce a recording and reproducing device which isfree from extraneous noises usually present in moving picture cam erasand projectors or similar machines wherein a continuous strip of film isinvolved.

The instrumentincludes among its more essential elements a sprocketwheel provided with teeth which mesh into the conventional perforationsof moving picture type film. If desired,- a

roller may be used instead of the sprocket wheel.

The rotation of the sprocket wheel propels the film forward in the usualmanner employed in moving picture cameras and projectors. cording headis provided with astylus, the point of which presses into the film toform the vibration groove. When the stylus is not being vibrated bysound pulsations, however, the forward movement of the film would causethe stylus to inscribe a straight groove on the film..

A cross section of the groove is roughly V-shaped with a depth ofapproximately .002 inch and a top width of approximately .003 inch.

The recording head is so constructed that when actuated by alternatingor interrupted current, the stylus vibrates transversely to the motionof the film, thus causing-the stylus to inscribe a wavy groove in thefilm, the number of waves corresponding to the frequency of the currentscausing vibration of the stylus. If these currents are modulated byfrequencies arising from the voice or musical instruments, the groovewill then be of a wavy pattern having a frequency corresponding to thefrequencyof the actuating currents and the sound waves modulating them.The amplitude of the recorded waves will bear a direct relationship tothe intensity of the sound waves so that by retracing the groove with apickup stylus and amplifying the currents induced thereby andreproducing them through a loud speaker, sounds will be reproduced infrequency and volume similar to the original recorded sound.

Among the more important elements of this device are the sprocket wheeland stylus, these Areto a recording head which controls the movementthereof while the sprocket is mounted on a spindle, in bearings; aflywheel is provided on the same spindle to drive the sprocket at auniform speed. A motor, having a governor, drives the flywheel;receiving and releasing reels carry the film; and rollers are providedto hold the film in operative relationship with the sprocket. A mountingmember is provided to carry the recording head, the head being adaptedto be moved transversely to the motion of the film in graduated steps inorder that a large number of closely spaced grooves may be recorded on asingle strip of film. The entire assembly is mounted ona base plate, thesame being carried in a portable carrying case.

This device will be understood in more detail by referring to theattached drawings in which like numbers refer to like parts.

Figure 1 is a perspective view of the device according to thisinvention;

Figure 2 is a top plan view of Figure 1 omitting the reels;

Figure 3 is a transverse, vertical sectional view on line 3-3 of Figure2, showing the pick-up V-notch in place;

Figure 4 is a longitudinal vertical sectional view, on line 4-4 ofFigure 1;

Figure 5 is a transverse, vertical sectional view, on line 55 of Figure4;

Figure 6 is a vertical longitudinal sectional view, on line 6.6 ofFigure 5;

Figure 7 is a fragmentary view of Figure 5, looking in the direction ofthe arrow 1 of Figure Figure 8 is a fragmentary side elevation showingthe pickup structure and its mounting means;

Figure 9 is a fragmentary rear elevation of Figure 10 is a fragmentaryvertical elevation,

partially in section, on line Ill-l0 of Figure 1.

Referring to the accompanying drawings, a box-like casing is provided onthe top of which there is provided a base plate or mounting member A onwhich most of the various elements are compactly and operativelymounted. The recording head 50 carries a stylus I, provided with arecording point, which is adapted to cut a groove in the film as it ismoved past the same in the direction of the arrow by the engagement ofthe sprocket 2 with the film. Movement of the stylus is controlled bythe mechanism included in the recording head 50. The sprocket consistsof a wheel bearing two rows of teeth,

a central cylinder.

- dies 8 each row engaging perforations in either side of the film, inthe conventional manner.

The construction of the sprocket is an important feature of theinvention. It may either be made of one piece or of two outer disks andIn either case the central cylindrical portion between the rows of teethis ground to a mirror finish and preferably hardened. The centralportion is left from one to a few thousandths of an inch larger indiameter than the two outer disk shaped portions which bear the two rowsof teeth. This construction has been found to facilitate theconformation of the film to the sprocket wheel and to minimize sprocketwheel noises.

The sprocket wheel teeth are formed with a base of such design that thetransverse dimensions of said base portion are slightly less than thedimensions of the film perforations so that as the film contracts andexpands with changes of temperature and to some extent with aging, thesprocket wheel will operate smoothly and silently in contact with thefilm at all usual temperatures and with film of various ages. Thesprocket is designed to operate successfully at room temperaturesranging from 45 to 95 degrees F., the sprocket wheel dimensions beingundersize sufficiently to accommodate the expansion and contraction ofthe film material within that range of temperature. .For practicalpurposes the base dimensions of the teeth may be considered to be 98%(or less) of the dimensions of the film perforations at normal roomtemperature.

Sprocketwheel 2 is also provided on one side with a fixed guide flangeand on the opposite side with a movable flange or guide plate 5 which isdished toward the sprocket center, the same bemg spring pressed againstthe edge of the film as it passes over the sprocket wheel by the springThe sprocket is mounted on a main spindle 3, on which a flywheel 4 isalso mounted, the flywheel being of such design that the central portlonconsists of a thin web or flange joining the hub and rim portions, themajor portion of the weight being concentrated near the periphery of thewheel. This flywheel is provided with a pulley I 2 which drives a springbelt member l3, and drlViIlg pulley M on the take-up or receiving reelIS. The flywheel spindle 3 is provided with conical, inwardly directedground and hardened bearings 1 at each end, into which are fittedcomplementary, conical, hardened, bearing spin- This type of hearing hasfour distinct advantages. First, it provides a simple means of taking upwear that occurs on the bearings; sec- 0nd, it keeps the main spindle,and consequently the sprocket, perfectly centered at all times, thuseliminating noise waves or change of pitch usually due to eccentricbearings; third, it permits a minimum of machine noises to betransmitted through the bearings, probably due' to the smallness of thetransmitting surface; and, fourth, the diameter being small, thevelocity of the frictional bearing surface is low and any noisegenerated is of low intensity. These bearing spindles are mounted inbearing posts I!) which are cast integrally with the base plate A. Setscrews H hold these hearings in place in the desired adjustment.

Removably supported on one end of the portable carrying case is an arm[9 which supports the receiving reel [6 on a rotatable shaft l5 drivenby the pulley I4. A bearing l 9a supported by arm l9 rotatably supportsshaft l5. Arm l9 and the bearing l a are preferably in one piece, andthe bearing axis is at right angles to the central axis of the arm is.

A key l7, pivotally mounted on a pivot la in a slot in the end of shaftl5, serves to lock the reel E6 to the shaft I 5 and against slipping offthe end thereof. Shaft 15 is formed with a flange thereon faced withsoft rubber or felt [5b mounted in an annular groove I5a in the flangeface. When the reel I6 is mounted on the shaft l5, one side thereof isdisposed against said rubber or felt. By such construction, vibrationsnormally arising from the reel vibrations attendant to reeling film aredamped out.

Arm I 9 is removably attached to the base A by means of a truncatedV-shaped end flange member which snugly fits a complementarily shapedgroove in a plate 20.

In packing the apparatus for carrying, the reel-carrying arms l9 and 26are removed from their supporting brackets, and packed in a suitablecarrying case. with the rest of the apparatus.

Guide rollers 2i and 22 are provided on the opposite side of thesprocketfrom receiving reel Hi to prevent the film from rubbing againstadjacent parts. These rollers are spaced .closely together, leaving onlya narrow slot between them and are mounted on stud shafts projectinghorizontally from the upright support 46.

Before the fllm passes through the narrow opening between the rollers 2iand 22, it passes over a guide plate 23 mounted on a block supported bybase plate A, said guide plate being provided with upstanding sideflanges 23a, which guide the film to eliminate any lateral movement andalign the film with sufficient accuracy to enable' the film perforationsto mesh with the sprocket wheel teeth at all times. The upper surface ofthe guide plate 23 is disposed below but substantially parallel to thefilm and is covered with felt or velvet material. As the film passesover the bed portion this material removes 'any dust from the under sideof the film, thus eliminating any dust grains between the film and thesmooth surface of the central portion of the sprocket wheel between therows of teeth, over which surface the recording takes place,

A weight 24 is provided, which is adapted to rest on the film over theplate 23 and between the upstanding flanges 23a, said weight beingprovided with an enlarged portion or transverse pin at its approach endwhich is adapted to contact the fianges to prevent the film carrying theweight forward. This is clearly shown in Figs. 1 and 4. The bottomsurface of the weight 24 is also covered with felt or velvet adapted toclean the upper or groove carrying side of the film, to remove any dustfrom said surface.

A supply reel 25 carrying the film to be grooved is mounted on a bracket26 at'the left of the device, as seen in Fig. 1. This reel 25 releasesits film to pass between the sprocket wheel and the stylus and on to thereceiving reel is. The supply reel 25 is removably supported on a shaft21 extending transversely from arm 26 and is held thereon by a pivotedkey 28. The arm 26 is supported by block 25a. in the same manner thatarm I9 is supported by block 20.

The opposite end of shaft 21 from that supporting the reel 25 isprovided with a driving pulley 3U driven by a spring belt 3|, driven bya pulley 32. Pulley 32 is driven by the rubber or rubber faced wheel 33;pulley 32 and wheel 33 being mounted on opposite ends of shaft 34.

When the device is in operation for recording'or reproducing, the pullof the sprocket wheel 2 on the film 9 causes the supply or releasingreel 25 to rotate in a clockwise direction. During such operation therewind driving wheel 33 is out of contact with the flywheel 4 (Fig. 2).For rewinding purposes, however, the rubber or rubber faced rewind wheelis pressed against the flywheel. The clockwise motion of the flywheelcauses a counterclockwise rotation of the rewind pulley 33, which inturn causes the reel 25 to rotate in a counterclockwise direction andrewind the film. During such operation, the film is not engaged by thesprocket 2 but is passed around it or a. releasable clutch member may beprovided be-. tween the sprocket and the shaft 3. I

When it is desired to bring the rewind pulley 33 into contact with theflywheel 4 and hold it there, there is provided a lever attached'by'apivot 36 to a base block49, see Fig. '6. Attached to the same block by apivot 31 is a frame structure composed of links 43 vertically disposed,the lower ends of which are rotatably pivoted at 31, one to each side ofthe base mem- .ber 49. The upper end of each link 43 is provided with'abearing which supports opposite ends of shaft 31 between the links 43.The pulley 32 and rewind rubber wheel 33 are attached to shaft 34, thethree pivoting as a, unit in the bearings provided in the upper ends oflinks 43. Lever 35 contains a slot 38. A pin 39 is attached to theinnermost link 43, projecting transversely therefrom and into this slot.The rotation of the lever 35 about its pivot 36 causes the pin 39 totransverse the length of the slot 38. Thus,

when the free end, of the lever is depressed, as shown at 35a (Fig. 6)'the pin 39 occupies the upper end of the slot at the end of suchmovement and the shaft 34 carrying rubber pulley 33 is simultaneouslyforced to the right against the flywheel 4. The upper end of the slot 38is provided with an offset portion, which is adapted to receive the pin39 when the end of the slot 38 is reached, thus holding the lever 35 inthis position until the free end of the lever is moved upwardly at whichtime the pin 39 is forced from the offset slot to disengage the rubberpulley from engagement with the flywheel.

To'assist in pressing pulley 33 toward flywheel 4, a leaf spring 4| heldin position by a holder 42 mounted in base block 40 is disposed to pressthe upper end of the outside link 43 toward the flywheel, see Figs. 2and 5. Y

An upstanding rib 46 is centrally mounted on the upper side of the baseplate A with its longitudinal-axis substantially parallel to thelongitudinal axis of the base plate and is secured by mounting screws49, as shown by Fig. 3; This central rib serves as a support for anumber of members hereinafter described.

Attached to one end of the central rib and at right angles thereto is atransversely extending guideway 41, Figs. 2, 4 and 8, provided withagroove, the cross-sectional shape of 'which is a truncated invertedV.-'

The recording and pick-up heads 50 and 5| are provided with suitableelectromagnetic means for converting varying electrical currents intomechanical movements of the stylus, or for converting movements orvibrations of the stylus to corresponding electrical currents, as iswell understood in this art.

The recording head 50 (Fig. 1) and pickup head 5| (Fig. .9) which areadapted to be substituted for each other, are removably mounted on acarriage 52 provided with a truncated Veshaped and tongue to permitinsertion of a take-up plate 53a (Fig. 4) which is adapted to be pressedagainst the side of the tongue 53 by screws 53b. Any wear in the tongueand. groove are taken up by tightening the screws 53b, thus permitting asnug fit between the tongue and groove at all times so as to preventundesirable play or wob-.

bling. The screws 531) may also serve,'if desired, to lock the carriagein adjusted position. v

The sound recording head 50, as clearly shown in Fig. 4, has a weight59a carried by an arm pivotally mounted at one end thereof. Such amounting affords an adjustable pressure for the groove forming stylus Iwhen acting on the film 9. The weight may be held in any desiredposition with respect to the head from that shown in Fig. 4 to 180 inthe opposite'direction, in which position it will be directly over thepickup head. The effective pressure exerted by the weight on the stylusdepends on the angular position of the weight, different angularpositions of the weight giving different horizontal components for thelever arm withjrespect to its fulcrum 56. The arm may be held in anydesired angular position by the supporting and locking bolts 59b clearlyshown in Figs. 1 through 5.

Vertically mounted on the carriage 52 are two standards 54, each beingdrilled to receive bearing spindles 55 and 56. Spindle 55 is held infixed position in its standard while the spindle 56 is adjustably heldin position in its standard by thumb screw 51. When the mechanism is tobe employed in recording, the recording head 59 is pivoted between thebearing spindles 55 and 56, the points of which are inserted intocomplementary recesses formed in bearing blocks 58, provided on thesides of the recording head 50, Fig. 5. When the mechanism is employedin a reproducing capacity, however, a sound pickup head 5| replaces therecording head shown in Fig. 9. The pickup head is also provided withbearings 58 similar to those on the recording head both in design andlocation.

Bearings for the pickup head are formed in either end of a pivot bar 59which supports the head, as is clearly shown in Fig. 9. The pickup head5| is attached to the block 59 by means of a swivel 66. Thus, whereasthe recording head is rigidly held against horizontal movement, the

pickup head is free to follow the course of the groove. This arrangementhas been found very suitable'to prevent the pickup needle from jumpingout of the groove.

The pickup head is also provided with a centering pin 61 (see Fig. 8)projecting from its forward end. This pin 61 is adapted to rest in anannular the reproducing needle E'IA fits into the recorded groove. Bythis means, the uncertainty of lateral position permitted by the swivelis'overcome and the pickup needle is lowered positively into its groove.Rigidly attached to the carriage 52 is an "upwardly projecting standard63 having a laterally extending bearing member 64 which pivotallysupports spindle 62. Projecting laterally from the end of spindle 62opposite groove 5| an operating handle 66 is attached, the same beingoperv able to manipulate the eccentric portion to lower needle 61A, Fig.8, into the sound groove on the film. A spring 65 (Fig. 3) is disposedabout spindle 62 and is adapted to take up any play or wear occurringbetween the eccentric portion and the adjacent end of bearing members64.

Also pivotally mounted on the central rib 46 is a lever 68, see Figs. 2and 4. This member is supported by a pivot member 69 and a range ofmovement of about 10 or in a vertical plane is afforded this lever.Laterally extending from the lever 68 are two spindle or shaft-likemembers H. Integrally formed on the shaft members H at the attachingends are stub ends, eccentric to the longitudinal axis of the spindlesin order that the spindles ll might be adjusted in location with respectto the lever by manipulating the eccentric ends in the lever 68.adjusted position by set screws l3, Fig. 1. Mounted on each spindle is aroller member 1!), held thereon by stop pins M. These rollers areadapted to press the film against the sprocket wheel 2. Spacedcircumferential grooves 12 (Fig. 2) are provided about the periphery ofeach roller to accommodate the teeth of the sprocket 2.

When film is to be introduced into the device so as to pass over thesprocket, the lever 18 is raised sufiiciently to lift the rollers 10away from the sprocket to permit the insertion of the film.

Also laterally extending from one vertical wall of the upstanding rib 46is a headed stop member 15 (Figs. 1 and 4) which determines the lowestextent to which the lever 68 descends. When the lever is resting on thestop member, the eccentric mountings of the spindles H are so adjustedthat the outer periphery of the rollers is spaced from the periphery ofthe sprocket wheel just sumciently to permit the passage of the filmtherebetween.

Lever 68 is controlled by cam 16 mounted upon a shaft 17 which, in turn,is rotatably mounted in a bearing provided in the rib 46. A laterallyextending stop member 8| (Fig. 4) limits the downward movement of thecam. Rigidly mounted on the shaft H, on the opposite side of the rib 46,by means of a set screw 19, isan operating lever 18 by means of whichthe cam '16 is manipulated. Elevation of the lever I8 will elevate thecam 16 which, in turn, elevates the free end of lever 58. The free endof the lever 68 is maintained in engagement with the stop 15 or the cam16 by means of a'tension spring 80 which also simultaneously serves tomaintain the roller members 10 in engagement with the film surface sothat the film is properly engaged by the sprocket Wheel.

Mechanism is also provided within the scope of this invention whereby alarge number of sound grooveslocated side by side may be recorded on thefilm and subsequently reproduced therefrom. The structure permittingthis includes a lever 84 mounted parallel to and below the base plate A,and pivoted to the base plate by a stub shaft 88 (Figs. 2 and 4)rotatably mounted in a bearing in base plate A and extending through thebase plate to the upper side thereof. The free end of the lever 84 has aprojection 85 extending upwardly therefrom having mounted thereon ablock-like member 86 which contains a bearing for an ad justmentmaintaining member 81. The end 85 of the lever 84 projects through anarcuate slot 82 in the base plate A. Adjacent the concave side of thisslot is a gauge member 83 having suitable indicia marked thereon andalso having suitable holes formed therein at regularly spaced intervalsThe spindles are held in into which the adjustment maintaining member 81is adapted to be inserted to hold any given adjustment. The adjustmentmember may be preferably spring-pressed so that its location in anygiven setting may be assured.

Rigidly mounted on the end of shaft 88 which extends above the baseplate A is a hub member 89. Projecting tangentially from the upper endof hub 89 is a finger-like member 90 extending substantially parallel tothe lever 84. Mounted substantially parallel to but spaced from thefinger 90 is a leaf spring member 90a. Vertically projecting downwardlyfrom the under side of the carriage 52 is a pin 9| which is engagedbetween the finger 90 and spring 90a, whereby movement of the spring andfinger will be directly and accurately transmitted to the pin 9!. Bymeans of this construction the leaf spring presses the pin 9| againstthe finger 90 and thus takes up any wear that might occur on the pinthrough long use. It is thus obvious that movement of the projection 85of lever 84 will be transmitted through pin 9!. Since the ratio of thedistance between pin 9| and shaft 88 and the distance between shaft 88and projection 85 is quite large, being 1 to 6 or 1 to 8, it will beclear that a relatively large movement of the projection 85 willcorrespondingly transmit a much smaller movement to the pin 9! oncarriage 52. Thus it will be seen that the relatively small spacingsbetween the adjusted positions which might be obtained on carriage 52and correspondingly on the recording head 50 and the pickup head 5| willenable this device to either produce or record from quite a plurality ofclosely spaced, substantially parallel grooves on the film 9 previouslymentioned.

Electrical power is supplied to the device through a plug member 44located on one end of the casing (Figs. 1 and 4) from whence it isconducted to a switch 45 and then to motor 92 suspended from theunderside of base plate A. The mounting means of the motor comprises aplate 93 disposed generally parallel to base plate A and havingvertically depending therefrom a somewhat crescent-shaped bracket member94 in which the motor 92 is 'pivotally mounted on spindle members 95 insuch a way as to permit partial rotation of the motor about saidspindles. The ends of the spindles are conical in shape and extend intorecesses in the motor housing complementary in shape to the ends of thespindles.

Plate 93 is suspended from vertically disposed rods 91 depending fromthe underside of plate A. Holes are provided'in plate 93 to receive rods91 about which spiral springs 96 are disposed between the base plate Aand plate 93 and between the latter and nuts mounted on the lower endsof rods 97. Suitable rubber shock absorbing members may be substitutedfor springs 96, if desired.

The main shaft 98 of the motor 92 extends from either end of the motorsufiiciently to accommodate the several elements about to be described.On the end of the motor shaft adjacent the flywheel 4 is mounted adriving pulley 93! adapted to engage the outer rim of the flywheel, thepulley preferably being made of rubber so as to insure eflicientfrictional contact with the flywheel. The pulley 89 is resiliently heldagainst the flywheel rim by means of a spring member H l which isattached at one end to a projection extending from the end of the motoradjacent the flywheel (see Figures 4 and 5) and at the other end to aprojection extending from the motor mounting plate 93. Due to the yokestructure 94 supporting the motor by means of spindles 95 the motor 92is adapted to be slightly rotated in the yoke as described above. Thespring Ili utilizes the advantage thus afforded by the motor'beingpivoted to constantly urge the pulley end of the motor and the pulley 99toward the rim of the flywheel.

On. the opposite end of the. motor shaft 90 from the pulley 99 ismounted a governor structure of a substantially conventional type,comprising leaf spring members I02 which are disposedsubstantially'parallel to the motor shaft.

when the motor is idle. These spring members are rigidly attached at oneof their endsto a supporting member which is affixed to the shaft 90 andmidway oftheir length each spring has attached thereto a circular weightmember Ilil.

The opposite ends of the spring members I02 from the ends attached tothe supporting member are connected to a plate-like member I00 whichserves the functionof a brake disk and the plane of the same istransverse to the axis of the shaft 98. Rigidly mounted on the motor.

casing adjacent the brake disk I00is a supporting plate I08 having alaterally extending arm I09 projecting therefrom and substantiallyparallel to the motor shaft. The outer end of arm I09 is provided with abearing which supports shaft I05. ,Rigidly mounted on shaft I05 is ayokelike member I04 which is disposed normally substantially parallelto'brake disk I00. The central portion of yoke I04 is rigidly attachedto the shaft I05 so that any movement imparted to the shaft willcorrespondingly be imparted to the yoke. The outer free ends of the yokesupport felt brake shoe members I03' adapted to bear against the brakedisk I00.

shaft gains in speed the weight members l0I are As the motor graduallythrown outwardly, thus shortening the distance between the ends of thesprings I02, thus urging the brake disk I00 in the direction of the endof the shaft carrying the governor: and against the brake shoe membersI03.

Also rigidly mounted on the shaft I05 is a bell crank member I06. Oneleg of the bell-crank is longer than the other and extends generallyparallel to the motor shaft. The second, shorter leg extendssubstantially perpendicular to the first leg andhas attached to thelower .end thereof a spring member I01. The opposite end of this springmember is attached to the plate I 08.

Such construction constantly pulls the lower, end

of the bell crank toward the plate member 08 and in doing so willlikewise urge the yoke 04; carrying the brake shoesfI03 toward the b kedisk I00. Movement of brake shoes in this direction, however, is limj dby means of a threaded stop member I I3 engaging the long arm of thebell crank lever I06. Member IN is supported by a bracket member IIOrigidly mounted to the opposite end of the motor from plate I08 by meansof threaded studs 00.. The bracket IIO has a portion extending-parallelto and over the upper portion of the motor casing which supports athreaded bearing portion In through which is threaded the stop memberH3. f

The stop member H3 has a knurled head -I I3 rigidly, affixed to itsupper end which is above the upper surface of the base plate or mountingmember A. Asuitable aperture is provided in the base plate A havingsufficient clearance with respect to the stop member II3 that it. notonly allows the stop member to pass therethrough but also affords itconsiderable lateral movement,-

whereby any vibrations of the motor or any movement of the motor due toits being pivoted about the .pinions 95 will not be transmitted to thebase plate or any of the structures supported thereby.

Surrounding the aperture in the base plate A p which accommodates thestop member H3 is a disk H5 having graduated indicia thereon, reading inframes per second of the film but any other reading may be indicatedthereon suchas revolutions per minute of the motor. Laterally extendingfrom one side of the stop member H3 is a pointer or indicating member II4 which is adapted to be used in conjunction with the .graduations onthe disk member I I5 to properly set the stop member I I3.

By virtue of the foregoing mechanism, the.

principal elements contributing to such elimina-' tion are the mountingof the motor on pinions 95 and supplementary thereto the mounting of themotor supporting plate 93 on either spring or rubber cushion members soas not to transmit vibration to the base plate which, in turn, supportsall of the other essential units of me'chanism of the device. In mostinstances where driving is transmitted from one member to another, thesame takes place through either rubber or rubber surfaced pulleys ordriving wheels, which tends to eliminate vibration and noise. Allsurfaces where there is rolling or sliding contact such as the outer rimof the flywheel, the spocket wheel drum, and the friction surface of thebrake disk I00 are highly polished and as smooth as it is practical toobtain so as to eliminate any vibrations which would otherwise be due toirregularities in such surfaces. The concentration of most of the weightof the flywheel in the rim thereof tends toassure a uniform angularvelocity of the It is also to be noted that the ratio between thediameters of the flywheel and the sprocket member is relatively large,thus affording considwhich would be transmitted to the sprocket member.Similarly, the comparatively lower velocity of the sprocket wheelperiphery compared to the flywheel velocity results in a minimum ofsprocket wheel noise. In this connection, vibration and the spindle andbearing structure provided at either end of the main shaft 3. Thespindle members are ground as near perfectly conical in shape aspossible and are hardened to a high degree. Since the bearings of theshaft 3 are located at the very extremity. of each end, a minimum ofvibration or wobble will be created or transmitted as a result of anyshaft vibration. Similarly, the

' bearing surfaces between the conical spindles and erable reduction inany small variations of speed as might possibly occur at the rim of theflywheel 7 noise is also greatly reduced due to the nature of her whilebeing moved.

Great care is also exercised in the production of the sprocket wheel.The cylindrical portion of the wheel between the two sections ishardened and ground to a polish mirror-like surface, thus affording aperfectly smooth floor on which the recording and reproduction takesplace. The dust removing members described above and provided on themembers 23 and 24 insure that no foreign particles will be disposedbetween the film and the mirror surface of the sprocket wheel whichmight create vibrations if permitted to become disposed between the filmand this surface. Also, the film pressure and guide rollers 10 areadapted to be adjusted in order to insure the proper positioning of thefilm against the mirror-like surface of the sprocket wheel and member 5.

In all of the reeling mechanism driving takes place through rubber orrubber surfaced driving Wheels and coil spring belts which tend toeliminate the transmission of vibrations and noise.

rollers are lowered only the proper distance and no more. Likewise,while being lowered, the end of the lever carrying the rollers isconstantly maintained in contact with Another advantageous feature ofthe above described construction resides in the mechanism for loweringthe pick-up mechanism-into contact with the film. This mechanisminvolves chefly the rotatable eccentric member 6| having the groovetherein which cooperates with the centermg arm 61 extending from thepick-up-head.

will take place without any jar or digging the, film.

Numerous other advantages are incorporated in the structure described,which will be obvious to those skilled in the art. Nor is it intended tolimit the scopeof this invention to the particular mechanism described,but it is intended to cover by this invention mechanism which might beperforming similar functions and accomplishing similar results.

We claim as our invention:

1. In a sound reproducing and recording mechanism, the combination of astylus and supporting head therefor for use with a record medium; asupport for said head and stylus comprising a carriage slidably mountedto position said stylus at a plurality of different transverse positionsrelative to the path of movement of said record medium, means to movesaid carriage comprising apivoted lever, means on one end of the leverengaging the carriage to move it in one direction and a second means onthe lever rcsiliently engaging the carriage to bias it into engagementwith the first mentioned means on the lever, and means on said leveropposite said carriage engaging means by which said lever may beoperated. I

2. In a sound reproducing and recording mechanism, the combination of astylus and supporting head therefor for use with a record medium; asupport for said head and stylus comprising a carriage slidably mounted.to position said stylus at a plurality of different transversepositions relative to the path of movement of said record medium, meansto move said carriage comprising a pivoted lever, means on one end ofthe lever-engaging the carriage to move it in one direction and a secondmeans on the lever resiliently engaging the carriage to bias it intoengagement with the first mentioned means on the lever, and operatingmeans on said lever opposite said carriage engaging means includingmeans to lock the lever and stylus in adjusted position.

3. In a sound reproducing and recording mechanism, the'combination of astylus and sup porting head therefor for use with a record medium; asupport for said head and stylus comprising a carriage slidably mountedto position said stylus at a plurality of different transverse positionsrelative to the path of movemen of said record medium, means to movesaid carriage comprising a pivoted lever, means on one end of the leverengaging the carriage to move it in one direction and a second means onthe lever resiliently engaging the carriage to bias it into engagementwith the first mentioned means on the lever, operating means on saidlever opposite said carriage engaging means including means to lock thelever and stylus in adjusted position, and indicia adjacent the path ofthe lever operating means.

4. In a sound reproducing and recording mechanism, the combination of astylus and supporting head therefor for use with a record medium, asupport for said head and stylus comprising a carriage slidably mountedto position said stylus at a plurality of different transverse positionsrelative to the path of movement of said record medium, means to movesaid carriage comprising a pivoted lever, means on one end of the leverengaging the carriage to move it in one direction and a second means onthe lever resiliently engaging the carriage to bias it into engagementwith the first mentioned means on the lever, operating means at theopposite end of said lever, said operating means also having lockingmeans associated therewith comprising a spring-pressed pin and a seriesof cooperating depressions to maintain the pivoted lever and stylus inadjusted position.

5. In a sound reproducing and recording mechanism, the combination of astylus and supporting head therefor for use with a record medium,

I a support for said head and stylus comprising a carriage slidablymounted to position said stylus at a plurality of difierent transversepositions relative to the path of movement of medium, means to move saidcarriage comprising a pivoted lever, one end of which is fork-like withone member of said fork resilient, said carriage having a member engagedbetween the members of said fork, whereby wear between the said recordrelatively moving parts will be automatically compensated, and operatingmeans on said lever opposite said carriage moving means.

6. In a sound reproducing and recording mechanism, the combination of astylus and supporting head therefor, for use with a record medium; asupport for said head and stylus comprising a carriage slidably mountedto position said stylus at a plurality of different transverse positionsrelative to the path of movement of said record medium, means to movesaid carriage. comprising a pivoted lever, means on one end of the leverengaging the carriage to move it in one direction and a second means.onthe lever resiliently engaging the carriage to bias it into engagementwith the first mentioned means on the lever, operating means at theopposite end of said lever,

the distance between the pivot of the lever and tin carriage engagingend being substantially less than the distance between the pivot and theoperating end of the lever, whereby a large movement at the operatingend will produce a much smaller movement at the carriage engage ing end,thus permitting very fine adjustments in the movement of the carriage tobe effected.

7. In a sound reproducing and recording mechanism, the combination of astylus and supporting head therefor for use with a record medium, asupport for said head and stylus comprising a base plate and a carriageslidably supported thereon to position said stylus at a plurality ofdifierent transverse positions relative to the path of movement of saidrecord medium, a bearing arranged on said base plate with the bearingaperture extending therethrough, means to move said carriage comprisinga lever mounted-in said bearing, said lever having one end projectingfrom one side of said bearing and arranged on one side of said baseplate to operatively engage said carriage, the opposite end of saidlever ex-- tending from said bearing and arranged on the opposite sideof said base plate from the first end of the lever, the latter end ofthe lever having operating means whereby the carriage may be moved todifierent adjusted positions.

8. In a sound reproducing and recording mech- 1 said carriage.comprising a lever pivoted in said bearing, means on one end of thelever disposed on one side of said base plate and engaging the carriageto move it in one direction and a second means on the lever resilientlyengaging the carriage to bias it into engagement with the firstmentioned meanson the lever, the opposite end of said lever extendingfrom said bearing and arranged on the opposite side of said base platefrom the first end of the lever, the latter end of the lever havingoperating means whereby the carriage may be moved to different adjustedpositions.'

FERDINAND von MADALER. WILLIAM L. WOOLF.

